Hey Paul... be sure you also reinstall the Alembic electronics when you change the PUPs. Based on your description of the current guts, I don't think they are Alembic. I don't know what series of Barts you have, but if they're high impedance (passive) you will NOT be able to just throw in some Alembic PUPs (all Alembic PUPs are low impedance). While Alembic makes beautiful instruments, I think you will find that it's the electronics that really set them apart from everyone else (opinion of course!!!).